personal theory: burnout is basically when you're expending more energy than than you're able to recover during rest -- over chronic timelines. that is, i think getting physical health right addresses many causes of burnout. getting your device and app use right addresses a set of others. finding ways to connect with your team, users, company mission addresses other potential problems; ie feeling alienated and on a futile or harmful mission is a great way to get burned out.
wrote about some of this here: https://vonnik.substack.com/p/state-changes-work-and-presenc...